Method of sulfonating organic compounds with chlorsulfonic acid in continuous operation



March 23, 1954 v, BLINQFF 2,673,211

METHOD OF SULFONATING ORGANIC CQMPOUNDS WITH CHLORSULFONIC ACID IN CONTINUOUS OPERATION Filed July 12, 1949 m A a M. M

lNl/E/V TOP Patented Mar. 23, 1954 METHOD OF SULFONATING ORGANIC COM- POUNDS WITH CHLORSULFONIC ACID IN CONTINUOUS OPERATION Vsevolod Blinofi, Neuilly-sur-Seine, France, assignor to Societe Anonyme dlnnovations Chimiques (lite: Sinnova ou Sadie, Meaux-Beauval,

France Application July 12, 1949, Serial No. 104,317

Claims priority, application France July 17, 1948 3 Claims.

Inconveniences are experienced in the sulphonation of organic compounds and particularly of fatty alcohols with chlorsulphonic acid C1SO3H whereby working in continuous operation on an industrial scale is made difiicult.

These inconveniences are mainly caused by creation of hydrochloric gas which is well known to be a very active corrosive agent, this corrosive activity being increased by the presence of acid sulphonation products.

A further inconvenience arises from the liberation of large amounts of heat which frequently must be absorbed in order to prevent the decomposition of the sulphonation products. Thus the necessity arises of providing cooling systems which unavoidably are in contact with the said very corrosive substances.

A further inconvenience, which is inherent in the very character of the reaction constituents, is caused by their frothing characteristics; this is particularly so, if fatty alcohols are used. The froth will considerably interfere with the heat exchange that is required for a satisfactory conduct of the invention. Moreover, the comparatively high boiling point of certain alcohols may also prevent a sufficient lowering of the temperature of the charge.

It is apparent from the above that many difficulties stand in the way of any method of sulphonation processes with chlorsulphonic acid, the main difiiculty being caused by the presence of considerable amounts of hydrochloric gas and acid sulphonation products.

Various methods have been suggested to eliminate the above described difiiculties.

It has been proposed to mix the compound to be sulphonated, e. g. a fatty alcohol, either as such or in solution in an inert solvent, directly with the chlorsulphonic acid and before being cooled and to remove the hydrochloric gas formed at the outlet of the cooler. The above mentioned inconveniences are not eliminated in this manner and the froth consisting of minute hydrochloric gas bubbles finely dispersed in the mass will not only strongly impede the gas flow but also interfere with the exchange of heat.

Attempts have been made to prevent the froth formation by mixing the reaction components intimately on a rapidly rotated disc whereby a film is produced and from which the film is whirled onto the cooled wall of the vessel. In this manner the reaction stage takes place during the passage of the reactants from the disc to the wall and partly takes place on the latter.

This invention is based on a difierent principle and aims at an'instantaneous removal of the reaction heat together with the hydrochloric. gas by dispersing the reaction constituents as finely as possible in an inert, preferably, gaseous medium where dispersion can be maintained for the comparatively short time which is required for the reaction.

In the performance of this method a compressed gas is used as the dispersion medium and by its expansion the reaction mixture is dispersed and the reaction product cooled.

It has already been proposed to use atomizing devices for the performance of certain exothermal reactions and for drying organic substances, particularly in those cases where the latter are sensitive to heat; thus the heat, the moisture and the solvent are carried away by the gas used as dispersion medium.

The instant method, however, differs from the art insofar as in addition to the removal of the reaction heat a balanced reaction is obtained by simultaneously removing one of the reaction products instantaneously, i. e. at the rate it is produced.

Moreover, reaction components react with each other as droplets carried along by the gas stream and not upon metal surfaces; consequently the latter are protected against corrosion the highly corrosive mixture of hydrochloric acid and an acid sulphonation product being separated into its constituents which individually are less corrosive.

In this manner the atomization effected in conformity with the invention, as described hereinafter, serves to remove the reaction heat and to separate a highly corrosive mixture into less corrosive components due to the instantaneous elimination and dilution of one of its constituents, this elimination serving to displace the reaction balance in a favorable manner.

The performance of the invention will now be described more in detail and with reference to the attached drawing.

The substance to be sulphonated, e. g. a fatty alcohol, which may be dissolved in an inert solvent, for instance, chloroform, is stored in the supply tank 2 and the chlorsulphonic acid is stored in the supply tank 5; these two substances are separately fed through valves 3 and 6 and flow meters (not shown) to the atomizer 9. The latter is at the same time supplied through valve 8 with a dry inert gas under a pressure which may vary from 1 to 50 kg/sq. cm. depending on the rate of the desired atomization. Obviously this atomization will prevent the formation of froth.

In the particular case where fatty alcohols are to be sulphonated the inert gas may, for instance, be air, carbonic acid, nitrogen or hydrogen.

The liquids are mixed by the expanded gas in the injector S and converted into minute droplets; the advance of these controlled droplets through the sulphonationvessel i9 is so controlled that at their arrival on the bottom of the vessel they are practically freed from hydrochloric acid. The gas should be used at such a pressure and quantity that the hydrochloric gas is removed completely while the heat generated during the reaction is immediately transmitted to the gaseous medium that surrounds the droplets.

A strip-per (not shown) is provided in order to remove the line vesicular particles carried oil by the gas mixture. The I-ICl-carrying gases are removed through pipe l2 and the acid sulphonation product through pipe i l.

Example: Industrial lauryl alcohol istreated as set forth hereinbefore at the rate of 100 kgs. anthour. The said alcohol is mixed and dispersed in the atomizer $3 with 65 kgs. of chlorsulphonic acid with the aid of 700 cubic meters of air per hour the having been compressed to 7 kgs. sq. cm. and cooled to 0 C.

In this manner 140 to 150 lags. of a viscous, brown water-soluble product result, which is practically entirely sulphonated. By neutralization in a conventional manner with either ammonia, or triethanolainine or sodium compounds are obtained that possess considerable frothing and wetting properties and that are comparable in all respects to those obtained in discontinuous operation.

With the aid of a plant as above described the process can be easily carried out and controlled. The manifold purpose aimed at, viz. the performance of the reaction, the removal of one of the undesired reaction icyproducts, the completion of the reaction and the removal of the evolved heat, is fully attained.

Many modifications or embodiments of the invention such as upward ejection of the mixture or into a vessel set at-any desired angle of slope, or the use of an inert solvent that will selectively retain the hydrochloric gas or the acid sulphonation product are embraced by the scope of the claims.

What I claim as my invention and desire to secure by Letters Patent is:

1. A method of sulphonating lauryl alcohol with chlorsulphonic acid, which consists in conducting separate fiows of each reactant in the liquid state into a. flow of an expanding compressed inert gas, whereby said components are converted into. droplets and react with each other in this state, are swept along by said stream of the expanding gas, whereby the reaction productis cooled and the formed reaction by-product is removed.

2. A method of sulphonating lauryl alcohol with chlorsulphonic acid, which consists in. conducting separate fiows of each reactant" in. the liquid state towards each other and blowingan inert compressed gas into the junction of said flows, thus atomizing the reactants into a mist in the ath of which the sulphonation reaction is completed, whereby the reaction product is cooled and the reaction Icy-product is removed.

3. A method as claimed in claim 1, and applying the lauryl alcohol to be sulphonated as a solution in an inert liquid solvent.

VSEVOLOD BLINOFF. 7

References. Cited in the file. of this patent UNITED STATESPATENTS Number Name Date 2,1812% Mills Jan. 16, I940 2,2142% Mills et a1 Sept. 10,1940

FOREIGN PATENTS Number Country Date 553,598 Great Britain May 27, 1943 

1. A METHOD OF SULPHONATING LAURY ALCOHOL WITH CHLORSULPHONIC ACID, WHICH CONSISTS IN CONDUCTING SEPARATE FLOWS OF EACH REACTANT IN THE LIQUID STATE INTO A FLOW OF AN EXPANDING COMPRESSED INERT GAS, WHEREBY SAID COMPONENTS ARE CONVERTED INTO DROPLETS AND REACT WITH EACH OTHER IN THIS STATE, ARE SWEPT ALONG BY SAID STREAM OF THE EXPANDING GAS, WHEREBY THE REACTION PRODUCT IS COOLED AND THE FORMED REACTION BY-PRODUCT IS REMOVED. 